Alessio Bernasconi

3D Biometrics for Hindfoot Alignment Using Weightbearing CT

Background: Hindfoot alignment on 2D radiographs can present anatomical and operator-related bias. In this study, software designed for weightbearing computed tomography (WBCT) was used to calculate a new 3D biometric tool: the Foot and Ankle Offset (FAO). We described the distribution of FAO in a series of data sets from clinically normal, varus, and valgus cases, hypothesizing that FAO values would be significantly different in the 3 groups. Methods: In this retrospective cohort study, 135 data sets (57 normal, 38 varus, 40 valgus) from WBCT (PedCAT; CurveBeam LLC, Warrington, PA) were obtained from a specialized foot and ankle unit. 3D coordinates of specific anatomical landmarks (weightbearing points of the calcaneus, of the first and fifth metatarsal heads and the highest and centermost point on the talar dome) were collected. These data were processed with the TALAS system (CurveBeam), which resulted in an FAO value for each case. Intraobserver and interobserver reliability were also assessed. Results: In normal cases, the mean value for FAO was 2.3% ± 2.9%, whereas in varus and valgus cases, the mean was −11.6% ± 6.9% and 11.4% ± 5.7%, respectively, with a statistically significant difference among groups (P < .001). The distribution of the normal population was Gaussian. The inter- and intraobserver reliability were 0.99 +/- 0.00 and 0.97 +/-0.02 Conclusions: This pilot study suggests that the FAO is an efficient tool for measuring hindfoot alignment using WBCT. Previously published research in this field has looked at WBCT by adapting 2D biometrics. The present study introduces the concept of 3D biometrics and describes an efficient, semiautomatic tool for measuring hindfoot alignment. Level of Evidence: Level III, retrospective comparative study.

Core decompression versus other joint preserving treatments for osteonecrosis of the femoral head: a meta-analysis

INTRODUCTION Osteonecrosis of femoral head (ONFH) leads to hip osteoarthritis (HOA); among joint preserving treatments (JPT), the role of core decompression (CD) is still debated. We assessed the efficacy of CD compared with all other JPT in delaying the natural osteonecrosis evolution to HOA. SOURCES OF DATA Following the PRISMA checklist, the Medline and Scopus databases were searched. Fifteen- to 70-year-old subjects with ONFH with a minimum follow-up of 24 months were considered. The outcomes evaluated were patient clinical status, radiographic progression and total hip arthroplasty (THA) or further surgery (FS) need. Risk ratio (RR) was calculated for every outcome reported. RCT, CCT and prospective studies were included. AREAS OF AGREEMENT A total of 12 studies (776 patients) met the inclusion criteria. Clinical outcome (RR = 1.14; 95% CI 0.58-2.32; P = 0.05), radiographic progression (RR = 1.64; 95% CI 1.14-2.35; P = 0.05) and the need for THA/FS (RR = 1.52; 95% CI 0.95-2.45; P = 0.05) suggested a slight superiority of other JPT compared with CD. AREAS OF CONTROVERSY High heterogeneity of the primary investigations was the main limitation of our study. GROWING POINTS The efficacy and effectiveness of core decompression for ONFH are, at best, no better than other joint preserving strategies. The more recent scientific evidence seems to suggest that such procedure is less successful than other joint preserving strategies. AREAS TIMELY FOR DEVELOPING RESEARCH Further studies are needed to identify the best therapeutic approach to the ONFH.

Treatment of the trapeziometacarpal osteoarthritis by arthroplasty with a pyrocarbon implant

PurposeTrapeziometacarpal (TM) osteoarthritis is the most common type of arthritis of the hand. To date, among surgical alternatives proposed, no one type has been proven superior to others. In this prospective study we evaluated the efficacy of treating arthroplasty with a latest-generation pyrocarbon implant (Pyrocardan).MethodsThirty-six patients with TM arthritis were treated using Pyrocardan implant arthroplasty. Results were evaluated through thumb radial and palmar abduction assessment, key pinch strength evaluation, thumb opposition assessment according to Kapandji classification, the visual analogue scale, the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and the Patient’s Satisfaction Index.ResultsThere was substantial pain reduction and a satisfying increase in range of motion and strength (p < 0.01) and improvement in DASH score (p < 0.01). Average Patient’s Satisfaction Index was 8 out of 10.ConclusionsTM arthroplasty with Pyrocardan implantation is a suitable option in treating Eaton-Littler grade II or III TM osteoarthritis.

Tendoscopy of Achilles, peroneal and tibialis posterior tendons: An evidence-based update

BACKGROUND Tendoscopy has been proposed in treating several conditions affecting tendons around the ankle. We reviewed literature to investigate the efficacy of Achilles, peroneal and tibialis posterior tendoscopy. METHODS Following the PRISMA checklist, the Medline, Scopus and EMBASE databases were searched, including studies reporting patients affected by disorders of Achilles, peroneal and tibialis posterior tendons and treated by tendoscopy (or tendoscopic-assisted procedures). The tendoscopic technique, rehabilitation protocol, clinical scores, patient satisfaction, success and failure rates and complications were evaluated. RESULTS Sixteen studies (319 procedures) dealt with Achilles tendoscopy, nine (108) and six (78) about peroneal and tibialis posterior, respectively. Wound healing, cosmetic results, complication rate, work and sport resumption delay were satisfactory. Clinical scores, classification methods and rehabilitation protocols adopted were heterogeneous. CONCLUSIONS The recent scientific evidence suggests that tendoscopy and endoscopic-assisted percutaneous procedures are a safe and effective treatment in chronic and acute disorders of tendons around the ankle.

Anterolateral Arthroscopic Posterior Subtalar Arthrodesis: The Surgical Technique.

The effectiveness of subtalar arthrodesis has been well documented in treating degenerative subtalar joint disease. The arthroscopic subtalar approach for arthrodesis has also been proved to give excellent results in terms of bone fusion rates and reduction of wound-related pain and complications. To date, the main concerns about arthroscopy have regarded incision-related neurologic complications such as lesions of the tibial, fibular, and sural nerves. In this context, we present a 2-portal lateral (anterior and middle) approach to arthroscopic subtalar arthrodesis, recently documented in the literature, that provides similar excellent access to the joint with a lower risk of nerve damage.

Fibular Intra-articular Resection During Arthroscopic Ankle Arthrodesis: The Surgical Technique

Ankle arthrodesis is still considered the gold standard in the treatment of advanced painful ankle osteoarthritis. More than 3 decades ago, it was performed under arthroscopy; thereafter, many authors have reported excellent results and a low complication rate. Despite the significant improvements in surgical techniques, nonunion remains a problematic and relatively frequent event. This is one of the reasons the research is constantly active in this field. Ten years ago, a fibular resection during ankle arthrodesis was, for the first time, described in the literature as a means to correct malalignment in varus cases. Nowadays, we perform a similar technique during all arthroscopic ankle arthrodeses, regardless of the kind of preoperative deformity (varus, valgus, or normal alignment). In this article, we describe the arthroscopic technique to perform a fibular intra-articular resection during arthroscopic ankle arthrodesis, joining the benefits of arthroscopic minimal invasiveness to the full joint contact gained after such a fibular osteotomy. In our opinion, this would be the only way through which full contact between the talar and tibial surfaces may be achieved.

Role of Tendoscopy in Treating Stage II Posterior Tibial Tendon Dysfunction

Background: Stage II tibialis posterior tendon dysfunction (PTTD) resistant to conservative therapies is usually treated with invasive surgery. Posterior tibial tendoscopy is a novel technique being used in the assessment and treatment of posterior tibial pathology. The aims of this study were (1) to clarify the role of posterior tibial tendon tendoscopy in treating stage II PTTD, (2) to arthroscopically classify spring ligament lesions, and (3) to compare the arthroscopic assessment of spring ligament lesions with magnetic resonance imaging (MRI) and ultrasonographic (US) data. Methods: We reviewed prospectively collected data on 16 patients affected by stage II PTTD and treated by tendoscopy. We report the reoperation rate and functional outcomes evaluated by comparing pre- and postoperative visual analogic scale for pain (VAS-pain) and the Short-Form Health Survey (SF-36; with its physical [PCS] and mental [MCS] components). Postoperative satisfaction was assessed using a VAS-satisfaction scale. One patient was lost to follow-up. Spring ligament lesions were arthroscopically classified in 3 stages. Discrepancies between preoperative imaging and intraoperative findings were evaluated. Results: At a mean of 25.6 months’ follow-up, VAS-pain (P < .001), SF-36 PCS (P = .039), and SF-36 MCS (P < .001) significantly improved. The mean VAS-satisfaction score was 75.3/100. Patients were relieved from symptoms in 80% of cases, while 3 patients required further surgery. MRI and US were in agreement with intraoperative data in 92% and 67%, respectively, for the tendon assessment and in 78% and 42%, respectively, for the spring ligament. Conclusions: Tendoscopy may be considered a valid therapeutic tool in the treatment of stage II PTTD resistant to conservative treatment. It provided objective and subjective encouraging results that could allow continued conservative therapy while avoiding more invasive surgery in most cases. MRI and US were proven more useful in detecting PT lesions than spring ligament tears. Further studies on PT could use this tendoscopic classification to standardize its description. Level of Evidence: Level IV, therapeutic study, case series.

Joystick of the Talus for Correcting Malalignment During Arthroscopic Ankle Arthrodesis: A Surgical Tip

Ankle arthrodesis has been widely reported as an effective solution in treating tibiotalar joint osteoarthritis. The arthroscopic tibiotalar approach for arthrodesis has also been proven to give excellent results in terms of bone fusion rates and reduction of wound-related pain and complications. Historically, ankle malalignment has represented one of the main contraindications for the arthroscopic procedure, but interestingly some investigators have shown that the coronal joint deformity may be addressed arthroscopically as well. Other investigators have also demonstrated that part of the valgus/varus is due to malrotation of the talus within the mortise; therefore, controlling the talar position becomes crucial for correcting more severe deformities. We present here a technique for correcting tibiotalar malalignment during arthroscopic arthrodesis in varus or valgus ankles, performed through a K-wire used as a joystick to manage the talar position on both the coronal and axial planes.

Weightbearing CT Analysis of Hindfoot Alignment in Chronic Lateral Ankle Instability: a Multivariate Analysis of 124 Feet

Category: Ankle, Hindfoot, Imaging, Ankle Instability Introduction/Purpose: Varus hindfoot deformity may increase the risk of chronic ankle instability (CAI).Weightbearing CT (WBCT) semi-automated measurements and built-in databases may contribute to investigate the relationship between clinical and radiographic data. The objective of this study was to analyze hindfoot alignment (HA) in relation with CAI in a series of patients using these new tools. We hypothesized that there would be a positive correlation between a varus morphotype and a history of CAI. Methods: This is a Level 3 retrospective comparative study of a continuous series of 124 feet (63 patients) referred from July to December 2016. and subsequently assessed by WBCT (PedCAT®, CurveBeam LLC). The measurement software (Talas®, Curvebeam LLC), gave HA as a value of Foot and Ankle Offset (FAO). This measures the offset between the center of the ankle joint and the median line of the foot joining the centers of the calcaneus and forefoot weight bearing surfaces. Data was prospectively saved in a database (CubeView®, CurveBeam, PA, USA). The definition of CAI was a history of at least 3 ankle sprains during a 6 months period. Exclusion criteria were medial instability and syndesmotic injuries (2 cases).A univariate analysis was conducted to study CAI against the following variables: gender (Fisher), BMI and FAO (Kurskal-Wallis). The significant variables were subsequently included in a multivariate logistic model. Results: Nineteen feet had CAI, in 12 patients. Gender (p=0.0467 –the proportion of women for patients with CAI was 72.3%, compared to 33.3% without CAI) and FAO (p=0 .0002) were significant in the univariate analysis. The mean FAO was respectively -1.40 (SD: 5.50) and 3.56 (SD: 5.31) with and without a history of CAI. No significant difference of age or BMI was shown. After verification of log-linearity between odds of CAI and FAO, the multivariate logistic regression adjusted for gender demonstrated a 15% increase of odds of CAI per unit increase of varus (adjusted Odds Ratio (CI95%): 0.858 (0.771-0.943) p=0.003), and no more significant effect of gender after adjustment on FAO (Odds ratio (CI95%) Female versus Male: 0.548 (0.185 -1.669) p=0.277). Conclusion: A positive linear relationship was found between Varus Hindfoot Alignment measured using a semi-automatic tool in WBCT and the odds ratio for Chronic Ankle Instability, thus confirming and quantifying previous findings. The recent development of semi-automatic measurements and prospective databases opens future perspectives for big data and multivariate analysis in foot and ankle pathology.

Reliability of Hindfoot Alignment Using Weightbearing CT Semi Automatic Software: an Analysis of 135 Feet

Category: Ankle, Hindfoot, Imaging Introduction/Purpose: Hindfoot Alignment (HA) on 2D radiographs presents anatomical and operator-related bias. In this study, weightbearing CT (WBCT) was used to measure HA using a semi-automatic software which gives HA as a value of Foot Ankle Offset (FAO) after selecting four landmarks (weight bearing points of first and fifth Metatarsals, Calcaneus and center of the ankle joint). We assessed the intra and interobserver reproducibility and the distribution of FAO values in a series of datasets from clinically normal, varus and valgus cases. We hypothesized that reproducibility would be excellent. Furthermore, FAO in normals should have a Gaussian distribution and be significantly different to the varus and valgus groups. Methods: In this level 3, retrospective comparative study, WBCT (PedCAT ®, CurveBeam LLC, Warrington, PA, USA) datasets were obtained from an existing database. The 135 feet were assessed by a senior foot and ankle surgeon as normal, varus or valgus (57, 38 and 40 respectively). Two surgeon investigators (one senior and one trainee) independently analyzed each case using a semi-automatic HA measurement tool (TALAS ™, CurveBeam LLC, Warrington, PA, USA). A third, independent investigator conducted the statistical analysis using Stata® Software. Results: The overall intraoberver and interobserver reliability were 0.99 ± 0.002 and 0.97 ± 0.02 respectively. In normal cases, mean value for FAO was 2.38% ± 2.96, whereas in varus and valgus cases mean was -11.67% ± 6.90 and 11.47% ± 5.79, respectively (p<0.001). The normal population had a Gaussian distribution with a Kolmogorov-Smirnov test > 0.8 Conclusion: This study reports excellent reliability and discriminative power of a semi-automatic 3D measurement tool for Hindfoot Alignment in WBCT.